textproduct: Quad Cities

KEY MESSAGES

- The active weather pattern will continue through Monday, with potential for strong to severe storms each calendar day and mainly at night. Confidence on the day by day areal coverage and timing remains low.

- The warm and more humid stretch will last through early Tuesday, before a strong cold front sweeps through the area bringing cooler conditions for the mid-week period.

SHORT TERM /THROUGH TONIGHT/

Issued at 300 AM CDT Sun May 17 2026

Regional radar loops and satellite imagery suggest two "bookend" MCV's rolling acrs the Midwest ATTM, one acrs the southwest half of the DVN CWA and another more upstream acrs NE/KS/MO/IA quad state region. Network VWP's showing these waves being fed by southwesterly 40-50+ KT LLJ flow impinging on their southern flanks. The one closer to home will continue to move northeast acrs the area through 6-7 AM with it's weakening shield of rain with some embedded thunder. The other one acrs far northwest MO is a little more vigorous and may still help some stronger storms to keep going with it's shear as it rolls acrs the northwestern CWA through mid to late morning. Some additional swaths of heavy rain also possible this morning with these two vortex's.

Then as longer wave upper troffiness adjusts acrs the northern Rockies, leeside llvl/sfc frontogenesis will look to organize acrs the central plains and northern MO RVR Valley. After the morning to midday convective debris clears, the area to be engulfed in the warm breezy sector to the lee of the upstream front. This should make for widespread highs in the low to mid 80s today and some humidity with sfc DPTs in the low to mid 60s. Temporary upper ridge bulge in between waves and an EML should make for a dry afternoon and evening, as MCS initiation tools all suggest this evening's new convection to take off acrs the MO RVR Valley and MN. A robust southwesterly 50 KT H85 MB jet is progged to maintain acrs the area, and the upstream storms will look to propagate east-southeastwrad into the CWA not until well after midnight into early Monday morning. Depending on cold pool propagation mechanics and other support, these banded lines of storms will probably be generally in a weakening mode as they make their way acrs the area toward sunrise Monday, but still some threat for damaging winds with some of the lines as they enter the western CWA. They probably will also be dumping rain at high rainfall rates, but a progressive nature to the storms should limit a flash flood threat. Low temps in the mid to upper 60s.

LONG TERM /MONDAY THROUGH SATURDAY/

Issued at 300 AM CDT Sun May 17 2026

Monday and Tuesday...A stronger cold front will look to organize upstream acrs the plains and Upper MO RVR Valley on Monday. It will be another day of having some convective debris and outflow boundaries to wash out and recover with southerly flow as the day progresses. Highs back in the 80s and mid to upper 60 DPTs will make for a nice CAPE pool locally with values over 3000 J/kg possible. A stronger digging upper trof on the cold front off to the west will look to light up strong convection acrs the far east central plains and mid MO RVR Valley by late Monday afternoon. Another scenario where this convection grows upscale into a linear MCS, and may have better support to maintain as a severe squall line as it propagates eastward acrs IA and toward the local area later Monday night. A situation that will have to be monitored over the next day and a half. Ensemble timing has the cold front sweeping through the area Tuesday morning, taking the convection with it off to the eats and southeast of the area. A cooler blustery post frontal day by Tuesday afternoon.

Wednesday through Saturday...The latest ensembles suggest high pressure regime to shunt the main storm track to the south of the region for mush of the mid to late week period. Cooler temps in the 60s moderating back to the 70s by Friday. The next main chance for precip may not come until Friday if the latest wave-handling by the ensembles is correct.

AVIATION /18Z TAFS THROUGH 18Z MONDAY/

Issued at 1237 PM CDT Sun May 17 2026

A deck of MVFR stratus over northern IA will begin to scatter out and lift north of CID/DBQ over the next 1-3 hours. Otherwise, VFR conditions will prevail with strong southerly winds occasionally gusting near 30kts this afternoon. Attention then turns to evolution of storms upstream over the Plains this evening and tonight. Latest model solutions keep this activity west of the area through at least 05z, before nearing the terminals. Mature storms should begin to decrease in strength prior to arrival, but TSRA probabilities are still high enough to maintain PROB30/prevailing groups tonight. Brief IFR/MVFR conditions are expected as storms roll through. In addition, strong low level winds will bring a marginal LLWS risk and have kept mention in the TAFs.

DVN WATCHES/WARNINGS/ADVISORIES

IA...None. IL...None. MO...None.